The vestibular and the vestibular ocular system will be investigated by recording from neurons extracellularly and intracellularly in the reticular formation, abducens nucleus, third nerve nucleus and vestibular nuclei during the course of natural vestibular stimulation or electrical stimulation of the labyrinth. Particular attention will be made to correlate neuronal activity with the quick phase of nystagmus or quick eye movements or the termination of the slow phase of nystagmus. The purpose is to determine neurons which immediately precede the eye motor neurons (premotor neurons) and those which act upon the premotor neurons.